Creating SVG files for paper piecing using Inkscape

September 12, 2009

Here is how I use Inkscape and coloring pages or line art to make svg files for paper piecing.  The image that I started with had nice black lines with no unwanted breaks.  I have a tutorial on tracing pale or colored  images here.


  1. Paste or import the image into Inkscape.
  2. Make sure the image is selected, then from the menu use Path/Trace bitmap.
  3. The “Trace bitmap” dialog box will appear.
    paper piecing01
  4. Any image with nice dark lines and a light background will be fine with the default settings, so click “OK”.
  5. The vector or “Path” will be lined up over the original image.
  6. Move the two apart.
  7. Press 4 on your keyboard to zoom to show all objects.
  8. You can either delete the image, or leave it on the side to use as a reference.  The Path will usually look smoother and sharper.  You can also look at the message bar at the bottom of the Inkscape window to determine if you have the image or the path selected.
  9. This is the point where you would either connect lines or separate them if needed.  See this post for more information on connecting lines.  I cover separating lines in this post.
  10. If you are using Inkscape 0.47 you need to use Path/Union to create a vector that SCAL will be able to use correctly.
  11. Select the Path (vector) and from the menu choose Path/Break apart.  The Path will become a solid black with several dashed bounding boxes.
    paper piecing02
  12. I like to select the outmost shape that will be the mat or base and move it to the side.
    paper piecing03
  13. If you only want to cut the file in two colors, you could stop at this point.  You could also select all of the non-base pieces and use Control K to Path/Combine.  The file will appear the same either way once imported into SCAL.
  14. If you have internal pieces that you want to cut in a different color, you will want to either view in outline mode (View/Display mode/Outline) or use a thin stroke (outline) and no fill.
  15. If there are pieces with inner cuts, select the piece and the inner cut, then Control K.  This combines the pieces into one for easy moving and doesn’t cause the problems in SCAL1 that Group does.
    paper piecing04
  16. For my example I will select all of the piece on the outside of the whistle to be one color and the inside pieces to be another.  You can color the pieces for a better idea of how the paper piecing will look, but it isn’t necessary and won’t show in SCAL.  Select a fill color by clicking on any of the color bars at the bottom of the Inkscape window while a piece is selected.
  17. I will also move all of the inside color pieces together to reduce paper waste.
  18. I like to line up smaller images horizontally, a habit I developed when I was using SCAL1 and cutting on a 6×12 mat.  This eliminates the need to try to size everything correctly once imported into SCAL1.
    paper piecing05
  19. Either arrange your pieces so that they will all fit on your cutting mat at the size you would like to cut them, or if you have SCAL2 you can group (Control G) each color to be in its own layer when imported into SCAL2.  See this post for more on using Group and SCAL2.
  20. Save the file and import into SCAL.

This is what the paper piecing would look like.  The small triangular piece under the whistle is probably too small to use unless this file is cut at a rather large size.

paper piecing06

Here is the svg file for the whistle.  This svg file can be used in either version of SCAL. This file is for personal use only. Feel free to link to this post, but the file is not to be shared or distributed in any way.

SCAL 2.0 Trace Image – Brightness settings

August 2, 2009

If you would like general information on the autotrace settings click here.  Today I am going to look at the SCAL 2.0 Autotrace Brightness setting in more detail.  Below is an image that I found online that I thought would be good for testing the settings.

1 fish

Bring up the Autotrace dialog box by either clicking on the Trace Image button or through the File menu.  The Brightness can have a value of 0-100 with a default of 50.  What happens when you increase or decrease this value?

SCAL trace 03

The image below was traced using the default brightness setting of 50.  Most of the black lines were traced except for the green fish.

SCAL trace 04

Trace again with a brightness of 40 and all of the black lines trace, but none of  the colors.

SCAL trace 05

Finally, trace with a brightness of 75.  More of the black lines are not traced.

SCAL trace 06

There was another fish in the original image, so I traced with the two higher  settings on that one too.  And got similar results from a brightness standpoint.

SCAL trace 07

Lower brightness numbers provide higher brightness/contrast in the trace.   If you have an image with colors that are too close in brightness try tracing with a lower number.  If you have a trace that is including too much, try increasing the brightness value.

Basic information on tracing in SCAL 2.0

August 1, 2009

Another new feature in SCAL 2.0 is the autotrace.  You can import images (bmp, jpg, gif, png, etc) directly into SCAL and trace them there.  With SCAL 2.0 open, either click on the “Trace Image” button at the top of the SCAL window, or from the menu select File/Trace Image.

SCAL trace 01

The autotrace dialog box appears.  Click on the “Browse” button to select the image you want to trace.  There are five settings you can either adjust or select to optimize your trace.

SCAL trace 02

  1. Brightness
    This adjusts what the trace will include and what it will ignore.
  2. Corner
    This adjusts how the corners are treated.
  3. Despeckle
    Use this setting if you have an image with stray dots and specks.  The larger the number the larger the spots it will remove.
  4. Optimize
    I believe this is like “Smoothing” in Inkscape.  If checked it gives smoother lines with less nodes.
  5. Break Apart Outlines
    Check this if  you would like to do some basic editing after you trace.  It will put each separate shape or line into  its own layer in the trace folder.  The layers can be moved, deleted, or hidden just like a layered svg.

You can use the Preview button to see the effect of any changes you made to the settings.  Click OK when you like the results.

Click here for a more in-depth look into the Brightness settings.